A new study could shake up our understanding of how Earth and the other planets in our solar system formed.

While scientists have widely accepted the idea that the planets formed from rocky asteroids, researchers have now found that they may instead have been built from ‘giant convecting mud balls.’

According to the study, ice-filled grains of cosmic dust in the early solar system may have melted as they were subjected to radioactive heat, creating globs of water and dust that became the precursors to larger planetary bodies.

While scientists have widely accepted the idea that the planets formed from rocky asteroids, researchers have now found that they may instead have been built from ‘giant convecting mud balls.’ A stock image is pictured

HOW EARTH GOT ITS PRECIOUS METALS

Earth has an unusually high proportion of precious metals near the surface, which is surprising, as they would usually be expected to settle down near the core of the planet.

Until now, this has been explained by the 'late veneer' theory, which suggests that foreign objects hit Earth, and in the process deposited the precious metals near the surface.

But, recent computer simulations from the Tokyo Institute of Technology considered the metal concentrations on Earth, the moon, and Mars, and found that a huge collision could have brought all the precious metals to Earth at once.

The researchers believe that this happened before the Earth's crust formed – around 4.45 billion years ago.

This suggests Earth's history was less violent than previously thought.

In the new study, researchers from Curtin University and the Planetary Science Institute conducted computer simulations to analyze the movement of rock grains and mud in carbonaceous chondrite asteroids.

This was done by applying a model known as the Mars and Asteroids Global Hydrology Numerical Model (MAGHNUM).

Carbonaceous chondrite asteroids are thought to be the building blocks of terrestrial planets, such as Earth.

While these objects would have had ice throughout their pores, and would have picked up fine grains of dust, the researchers point out that there were no processes present that would have lithified – or transformed to stone – the material once the ice melted.

So, ‘it would have been a mud, rather than a rock,’ the researchers proposed in a paper published to Science Advances.

The simulations lined up with this idea, showing that many of the asteroids that are thought to have transported water and organic material to the early planets were likely not made of solid rock, as previously thought.

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And, the mud would have helped to moderate temperature inside the glob of water and dust grains, making it more consistent throughout.

This scenario would also allow the ‘mud balls’ to hold onto the primitive chemistry of the materials inside.

‘The assumption has been that hydrothermal alteration was occurring in certain classes of rocky asteroids with material properties similar to meteorites,’ said senior scientists Bryan Travis.

In the new study, researchers from Curtin University and the Planetary Science Institute conducted computer simulations to analyze the movement of rock grains and mud in carbonaceous chondrite asteroids. One such temperature map is pictured above

The simulations lined up with this idea, showing that many of the asteroids that are thought to have transported water and organic material to the early planets were likely not made of solid rock, as previously thought

‘However, these bodies would have accreted as a high-porosity aggregate of igneous clasts and fine-grained primordial dust, with ice filling much of the pore space.

‘Mud would have formed when the ice melted from heat released from decay of radioactive isotopes, and the resulting water mixed with fine-grained dust.’

According to the researchers, the new findings have implications for the understanding of how Earth originated 4.6 billion years ago.

And, they could even help to guide the search for other habitable planets.

The research adds new insight to the processes that transported water and other organic material to our own planet, and the other planets in our solar system.